Today, people commonly use messaging services over the Internet to communicate with each other. For example, a person may create a list of friends to whom they wish to communicate. Each friend has a unique user id that appears on the list. When the friend is online, the friend's user id is displayed in a manner such that the person knows the friend is available to communicate. The person may then initiate a “chat” session with the friend and exchange messages, commonly referred to as instant messages (IM). Additional friends may be added to the “chat” session resulting in a multi-party “chat” session having multiple people communicating with each other.
While having a multi-party “chat” session is convenient, users are becoming more interested in being able to see the other people and in experiencing a more “real-life” like experience, rather than typing messages. Unfortunately, providing a multi-party video conferencing system presents many challenges. One challenge is designing a system that can handle both the high bandwidth demand of the video conferencing application and the heterogeneity of Internet users. Another challenge is managing the communication among the multiple parties.
Many of the multi-party video conferencing systems only operate on a local area network (LAN). The following are a couple of multi-party video conferencing systems that operate over a LAN: 1) MERMAID described in an article by K. Watanabe et al. entitled “Distributed Multiparty Desktop Conferencing System: MERMAID” published in Proceedings of the Conference on Computer-Supported Cooperative Work, Los Angeles, Calif., September 1990; and 2) an article by Mike Macedonia and Don Bruzman entitled “MBONE, the Multicast Backbone” published in IEEE Computer, April 1994. Because these systems operate on a LAN, the bandwidth issue is not as problematic because the systems may utilize a multicast feature within the hardware to reduce the amount of data that is sent over the LAN. Unfortunately, the IP multicast enabled router is not universally deployed on the Internet.
Even though the hardware multicast feature is not universally deployed on the Internet, there have been some attempts at implementing a multi-party video conferencing system on a Wide Area Network (WAN). One system, commonly referred to as IVISIT produced by iVisit LLC in Santa Monica, Calif., is a server-based communication tool. IVISIT requires central servers that are accessible by the users at all times. The central servers perform membership registration and verification. Users interact with the central server when setting up their audio/video sessions with other users identified on their list of friends. While IVISIT allows a user to make multiple connections and view multiple videos at the same time, the system is not ideal. In one mode, the user must manually make each of the desired connections. In another mode, multiple parties may send instant messages to each other within a single chat room, but when video is desired, the video communication is based on an independent one-to-one connection. Thus, IVISIT does not provide the type of multi-party video conferencing system that the general public desires.
Another system, commonly referred to as WEBEX produced by WebEx Communication, INC. of San Jose, Calif., provides online meeting services for global businesses. The services include application sharing, white board, and video conferencing. WEBEX includes a number of switching centers worldwide for routing communications among the end users. While this strategy is efficient when there are a large number of simultaneous video conferences, WebEx is too costly for small-scale personal communications.
As described above, while having a server handle the communication is effective for large-scale enterprises, the server-based systems have several drawbacks for operating with small-scale personal communications. One drawback is the expense of purchasing and maintaining a server. Another disadvantage is the bottleneck created by using a central server. Thus, until now, there has not been a satisfactory solution for a multi-party video conferencing system suitable for use by the general public.